MATHEMATICS 4736 Decision Mathematics 1

Transcription

1 ADVANCED SUBSIDIARY GCE MATHEMATICS 4736 Decision Mathematics 1 QUESTION PAPER Candidates answer on the Printed Answer Book OCR Supplied Materials: Printed Answer Book 4736 List of Formulae (MF1) Other Materials Required: Scientific or graphical calculator Tuesday 22 June 2010 Afternoon Duration: 1 hour 30 minutes INSTRUCTIONS TO CANDIDATES These instructions are the same on the Printed Answer Book and the Question Paper. Write your name clearly in capital letters, your Centre Number and Candidate Number in the spaces provided on the Printed Answer Book. The questions are on the inserted Question Paper. Write your answer to each question in the space provided in the Printed Answer Book. Additional paper may be used if necessary but you must clearly show your Candidate Number, Centre Number and question number(s). Use black ink. Pencil may be used for graphs and diagrams only. Read each question carefully and make sure that you know what you have to do before starting your answer. Answer all the questions. Do not write in the bar codes. You are permitted to use a graphical calculator in this paper. Give non-exact numerical answers correct to 3 significant figures unless a different degree of accuracy is specified in the question or is clearly appropriate. INFORMATION FOR CANDIDATES This information is the same on the Printed Answer Book and the Question Paper. The number of marks is given in brackets [ ] at the end of each question or part question on the Question Paper. You are reminded of the need for clear presentation in your answers. The total number of marks for this paper is 72. The Printed Answer Book consists of 12 pages. The Question Paper consists of 8 pages. Any blank pages are indicated. INSTRUCTION TO EXAMS OFFICER / INVIGILATOR Do not send this Question Paper for marking; it should be retained in the centre or destroyed. OCR 2010 [M/102/2697] OCR is an exempt Charity 2R 0B10 Turn over

2 2 1 Owen and Hari each want to sort the following list of marks into decreasing order (i) Owen uses bubble sort, starting from the left-hand end of the list. (a) Show the result of the first pass through the list. Record the number of comparisons and the number of swaps used in this first pass. Which marks, if any, are guaranteed to be in their correct final positions after the first pass? [4] (b) Write down the list at the end of the second pass of bubble sort. [1] (c) How many more passes are needed to get the value 95 to the start of the list? [1] (ii) Hari uses shuttle sort, starting from the left-hand end of the list. Show the results of the first and the second pass through the list. Record the number of comparisons and the number of swaps used in each of these passes. [4] (iii) Explain why, for this particular list, the total number of comparisons will be greater using bubble sort than using shuttle sort. [2] Shuttle sort is a quadratic order algorithm. (iv) If it takes Hari 20 seconds to sort a list of ten marks using shuttle sort, approximately how long will it take Hari to sort a list of fifty marks? [2] 2 A simple graph is one in which any two vertices are directly connected by at most one arc and no vertex is directly connected to itself. A connected graph is one in which every vertex is joined, directly or indirectly, to every other vertex. A simply connected graph is one that is both simple and connected. (i) Explain why it is impossible to draw a graph with exactly three vertices in which the vertex orders are 2, 3 and 4. [1] (ii) Draw a graph with exactly four vertices of orders 1, 2, 3 and 4 that is neither simple nor connected. [2] (iii) Explain why there is no simply connected graph with exactly four vertices of orders 1, 2, 3 and 4. State which of the properties simple and connected cannot be achieved. [2] (iv) A simply connected Eulerian graph has exactly five vertices. (a) Explain why there cannot be exactly three vertices of order 4. [1] (b) By considering the vertex orders, explain why there are only four such graphs. Draw an example of each. [3] OCR Jun10

3 3 3 The constraints of a linear programming problem are represented by the graph below. The feasible region is the unshaded region, including its boundaries. y x (i) Write down the inequalities that define the feasible region. [3] The objective is to maximise P 1 = x + 6y. (ii) Find the values of x and y at the optimal point, and the corresponding value of P 1. [3] The objective is changed to maximise P k = kx + 6y, where k is positive. (iii) Calculate the coordinates of the optimal point, and the corresponding value of P k when the optimal point is not the same as in part (ii). [2] (iv) Find the range of values of k for which the point identified in part (ii) is still optimal. [2] OCR Jun10 Turn over

4 4 4 The network below represents a small village. The arcs represent the streets and the weights on the arcs represent distances in km. E 0.3 A 0.5 B 0.1 D C 0.35 F G (i) Use Dijkstra s algorithm to find the shortest path from A to G. You must show your working, including temporary labels, permanent labels and the order in which permanent labels are assigned. Write down the route of the shortest path from A to G. [5] Hannah wants to deliver newsletters along every street; she will start and end at A. (ii) Which standard network problem does Hannah need to solve to find the shortest route that uses every arc? [1] The total weight of all the arcs is 3.7 km. (iii) Hannah knows that she will need to travel AB and EF twice, once in each direction. With this information, use an appropriate algorithm to find the length of the shortest route that Hannah can use. Show all your working. (You may find the lengths of shortest paths between vertices by inspection.) [5] There are street name signs at each vertex except for A and E. Hannah s friend Peter wants to check that the signs have not been vandalised. He will start and end at B. The table below shows the complete set of shortest distances between vertices B, C, D, F and G. B C D F G B C D F G (iv) Apply the nearest neighbour method to this table, starting from B, to find an upper bound for the distance that Peter must travel. [2] (v) Apply Prim s algorithm to the matrix formed by deleting the row and column for vertex G from the table. Start building your tree at vertex B. Draw your tree. Give the order in which vertices are built into your tree and calculate the total weight of your tree. Hence find a lower bound for the distance that Peter must travel. [4] OCR Jun10

5 5 Jenny is making three speciality smoothies for a party: fruit salad, ginger inger and high C. 5 Each litre of fruit salad contains 600 calories and has 120 mg of sugar and 100 mg of vitamin C. Each litre of ginger inger contains 800 calories and has 80 mg of sugar and 40 mg of vitamin C. Each litre of high C contains 500 calories and has 120 mg of sugar and 120 mg of vitamin C. Jenny has enough milk to make 5 litres of fruit salad or 3 litres of ginger inger or 4 litres of high C. This leads to the constraint 12x + 20y in which x represents the number of litres of fruit salad, y represents the number of litres of ginger inger and represents the number of litres of high C. Jenny wants there to be no more than 5000 calories and no more than 800 mg of sugar in total in the smoothies that she makes. (i) Use this information to write down and simplify two more constraints on the values of x, y and, other than that they are non-negative. [4] Jenny wants to maximise the total amount of vitamin C in the smoothies. This gives the following objective. Maximise P = 100x + 40y (ii) Represent Jenny s problem as an initial Simplex tableau. Use the Simplex algorithm, choosing the first pivot from the column and showing all your working, to find the optimum. How much of each type of smoothie should Jenny make? [13] (iii) Show that if the first pivot had been chosen from the x column then the optimum would have been achieved in one iteration instead of two. [5] OCR Jun10

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8 8 Copyright Information OCR is committed to seeking permission to reproduce all third-party content that it uses in its assessment materials. OCR has attempted to identify and contact all copyright holders whose work is used in this paper. To avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced in the OCR Copyright Acknowledgements Booklet. This is produced for each series of examinations, is given to all schools that receive assessment material and is freely available to download from our public website ( after the live examination series. If OCR has unwittingly failed to correctly acknowledge or clear any third-party content in this assessment material, OCR will be happy to correct its mistake at the earliest possible opportunity. For queries or further information please contact the Copyright Team, First Floor, 9 Hills Road, Cambridge CB2 1GE. OCR is part of the Cambridge Assessment Group; Cambridge Assessment is the brand name of University of Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge. OCR Jun10

9 ADVANCED SUBSIDIARY GCE MATHEMATICS 4736 Decision Mathematics 1 PRINTED ANSWER BOOK Candidates answer on this Printed Answer Book OCR Supplied Materials: Question Paper 4736 (inserted) List of Formulae (MF1) Other Materials Required: Scientific or graphical calculator Tuesday 22 June 2010 Afternoon Duration: 1 hour 30 minutes * * * * Candidate Forename Candidate Surname Centre Number Candidate Number INSTRUCTIONS TO CANDIDATES These instructions are the same on the Printed Answer Book and the Question Paper. Write your name clearly in capital letters, your Centre Number and Candidate Number in the spaces provided on the Printed Answer Book. The questions are on the inserted Question Paper. Write your answer to each question in the space provided in the Printed Answer Book. Additional paper may be used if necessary but you must clearly show your Candidate Number, Centre Number and question number(s). Use black ink. Pencil may be used for graphs and diagrams only. Read each question carefully and make sure that you know what you have to do before starting your answer. Answer all the questions. Do not write in the bar codes. You are permitted to use a graphical calculator in this paper. Give non-exact numerical answers correct to 3 significant figures unless a different degree of accuracy is specified in the question or is clearly appropriate. INFORMATION FOR CANDIDATES This information is the same on the Printed Answer Book and the Question Paper. The number of marks is given in brackets [ ] at the end of each question or part question on the Question Paper. You are reminded of the need for clear presentation in your answers. The total number of marks for this paper is 72. The Printed Answer Book consists of 12 pages. The Question Paper consists of 8 pages. Any blank pages are indicated. OCR 2010 [M/102/2697] OCR is an exempt Charity 2R 0B10 Turn over

10 2 1 (i) (a) 1 (i) (b) 1 (i) (c) OCR 2010

11 3 1 (ii) 1 (iii) 1 (iv) OCR 2010 Turn over

12 4 2 (i) 2 (ii) 2 (iii) OCR 2010

13 5 2 (iv) (a) 2 (iv) (b) OCR 2010 Turn over

14 6 3 (i) 3 (ii) 3 (iii) 3 (iv) OCR 2010

15 7 4 (i) Key: Order of becoming permanent Permanent label Temporary labels Do not cross out your working values (temporary labels) E A 0.5 B 0.1 D 0.2 F C G There is a spare copy of the network below. E A 0.5 B 0.1 D 0.2 F C G OCR 2010 Turn over

16 8 4 (ii) 4 (iii) OCR 2010

17 9 4 (iv) B C D F G B C D F G (v) B C D F B C D F B D F C OCR 2010 Turn over

18 10 5 (i) 5 (ii) OCR 2010

19 11 5 (ii) (continued) 5 (iii) OCR 2010

20 12 PLEASE DO NOT WRITE ON THIS PAGE Copyright Information OCR is committed to seeking permission to reproduce all third-party content that it uses in its assessment materials. OCR has attempted to identify and contact all copyright holders whose work is used in this paper. To avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced in the OCR Copyright Acknowledgements Booklet. This is produced for each series of examinations, is given to all schools that receive assessment material and is freely available to download from our public website ( after the live examination series. If OCR has unwittingly failed to correctly acknowledge or clear any third-party content in this assessment material, OCR will be happy to correct its mistake at the earliest possible opportunity. For queries or further information please contact the Copyright Team, First Floor, 9 Hills Road, Cambridge CB2 1GE. OCR is part of the Cambridge Assessment Group; Cambridge Assessment is the brand name of University of Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge. OCR 2010